Scanning field angle expanding device and laser radar

Abstract

The utility model provides a scanning field angle expanding device and a laser radar. The scanning field angle expanding device comprises a rotating mirror and at least one optical wedge reflecting mirror, wherein at least one optical wedge reflector is arranged on at least one reflecting surface of the rotating mirror; according to the utility model, the light beam can be reflected through the optical wedge reflector, the view field angle of the reflected light beam is increased, the purpose of enlarging the scanning view field angle is realized, and the size of the device is far smaller than that of other optical systems under the conditions of the same view field angle and the same light source size, so that the required installation space is smaller, and the cost is lower. Different using requirements can be met, the size of the whole device can be reduced, the whole device can be installed and used in a small space, the space layout is more flexible and efficient, the whole device is small, the material using aspect, the manufacturing process aspect and the like are relatively simplified, and therefore the production cost is reduced.

Description

Technical Field

[0001] This application belongs to the technical field of laser scanning, and particularly relates to a scanning field of view expansion device and a lidar. Background Art

[0002] With the rapid development of automotive technology in recent years, in-vehicle lidar, as an important sensing component, is widely used in the field of autonomous driving. Existing laser scanning mostly expands the number of laser beams by setting a large number of lasers, and then obtains a large field of view. However, the cost increases, and the occupied space is large, resulting in a large volume of the device, which is inconvenient for installation and use. Summary of the Utility Model

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art or related technologies.

[0004] To solve the above problems, a first aspect of this application provides a scanning field of view expansion device, including: a rotating mirror and at least one wedge reflector; wherein, at least one of the wedge reflectors is disposed on at least one reflecting surface of the rotating mirror. The wedge reflector includes a first surface and a second surface, the rotating mirror is connected to the second surface of the wedge reflector, and the first surface is a beam splitting surface; the second surface is a reflecting surface.

[0005] Optionally, a first film layer is disposed on the first surface, and the first film layer is a beam splitting film;

[0006] And / or,

[0007] A second film layer is disposed on the second surface, and the second film layer is a reflecting film.

[0008] Optionally, two wedge reflectors are symmetrically distributed along the central axis on the same reflecting surface of the rotating mirror. Both of the two wedge reflectors include a front surface and a rear surface, and the same reflecting surface of the rotating mirror is respectively connected to the rear surfaces of the two wedge reflectors; the central axis is perpendicular to the rotating axis of the rotating mirror; along the direction from the edge of the rotating mirror to the central axis, the thickness of the wedge reflector gradually decreases.

[0009] Optionally, a third film layer is disposed on the front surface, and the third film layer is a reflecting film.

[0010] Optionally, the two optical wedge mirrors are symmetrically distributed about the central axis on the same reflecting surface of the rotating mirror. A connecting mirror is disposed between the two optical wedge mirrors. Each of the two optical wedge mirrors includes a front surface and a rear surface. The same reflecting surface of the rotating mirror is respectively connected to the rear surfaces of the two optical wedge mirrors and the connecting mirror; the central axis is perpendicular to the axis of rotation of the rotating mirror; along the edge of the rotating mirror towards the central axis, the thickness of the optical wedge mirror gradually decreases.

[0011] Optionally, a fourth film layer is disposed on the front surface, and the fourth film layer is a reflective film.

[0012] Optionally, at least one optical wedge mirror is disposed on each reflecting surface of the rotating mirror.

[0013] Optionally, the optical wedge angle of the optical wedge mirror is 0° ≤ β ≤ 10°.

[0014] The second aspect of the present application further provides a lidar, including the scanning field of view angle expansion device disclosed in any of the above technical solutions; thus, the lidar has all the features and beneficial effects disclosed in any of the above technical solutions, which will not be elaborated herein.

[0015] Beneficial effects

[0016] In the embodiments of the present utility model, a scanning field of view angle expansion device and a lidar are provided. The optical wedge mirror can reflect the light beam and increase the field of view angle of the reflected light beam, achieving the purpose of expanding the scanning field of view angle. Under the conditions of the same field of view angle and light source size, the volume of the present device is much smaller than that of other optical systems, which makes the required installation space smaller, can meet different usage requirements, can also reduce the size of the overall device, and realize the installation and use of the overall device in a smaller space, making the space layout more flexible and efficient. The relatively small size of the overall device simplifies the material use, manufacturing process, etc., thereby reducing the production cost. Description of the drawings

[0017] Figure 1 It is an installation structure diagram of an embodiment of the lidar of the present utility model;

[0018] Figure 2 It is an installation structure diagram of the second embodiment of the lidar of the present utility model;

[0019] Figure 3 It is a light ray schematic diagram of an embodiment of the scanning field of view angle expansion device of the present utility model;

[0020] Figure 4 It is a light ray schematic diagram of another embodiment of the scanning field of view angle expansion device of the present utility model;

[0021] Figure 5 This is the installation structure diagram of the third embodiment of the lidar of the present utility model.

[0022] The reference signs in the drawings are shown as:

[0023] 1. Rotating mirror; 2. Prismatic reflector; 3. First film layer; 4. Second film layer; 5. Third film layer; 6. Connecting mirror; 7. Fourth film layer. Specific embodiments

[0024] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.

[0025] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, "a plurality" means two or more unless otherwise specifically defined.

[0026] In the present application, unless otherwise clearly specified and limited, the terms "installation", "connection", "connection", "fixation", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0027] The following describes the preferred embodiments of the present utility model with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present utility model and are not used to limit the present utility model.

[0028] Refer to in combination Figures 1-5As shown in the figure, an apparatus for expanding the scanning field of view according to an embodiment of the present application includes: a rotating mirror 1 and at least one optical wedge mirror 2; wherein, at least one of the optical wedge mirrors 2 is disposed on at least one reflecting surface of the rotating mirror 1. The optical wedge mirror 2 includes a first surface and a second surface. The rotating mirror 1 is connected to the second surface of the optical wedge mirror 2. The first surface is a beam splitting surface; the second surface is a reflecting surface.

[0029] The outer side surface of the optical wedge mirror 2 facing away from the rotating mirror is the first surface, which is in contact with the external environment and is used for beam splitting. The light beam incident on the first surface is semi-transmissive and semi-reflective. The surface of the optical wedge mirror 2 connected to the rotating mirror 1 is the second surface; the second surface is a reflecting surface, which is used for reflecting the light transmitted through the first surface. Thus, through the first surface and the second surface, the angle of the light beam exiting the expansion device is increased compared to the angle of the incident light.

[0030] Among them, the beam splitting and reflecting functions of the first surface and the second surface can be realized by selecting special material optical materials or by coating. As Figure 3 shown in the figure, it is assumed that a first film layer 3 is installed on the first surface and a second film layer 4 is installed on the second surface. The first film layer 3 is a beam splitting film and the second film layer 4 is a reflecting film. Coating can improve the light transmittance and reflection performance of the optical element, improve the imaging quality and the utilization rate of light, and effectively block the erosion of external corrosive substances. The beam splitting ratio of the beam splitting film can be determined according to the design requirements, and can be a fixed beam splitting ratio or a variable beam splitting ratio.

[0031] When the light beam emitted by the outer light source irradiates the first film layer 3, the first film layer 3 can reflect a part of the irradiated light beam to form a reflected light, and the other part passes through the first film layer 3 to form a transmitted light. The transmitted light irradiates the second film layer 4, and the second film layer 4 can reflect it.

[0032] For example, when the light beam with a first initial field of view angle of θ1 irradiates the first film layer 3, the first film layer 3 divides the light beam into a reflected light and a transmitted light. The first film layer 3 directly reflects the reflected light to form a light beam scanning with a field of view angle of θ1. The transmitted light passing through the first film layer 3 is incident on the second surface. Due to the existence of the optical wedge angle β, the second film layer 4 on the second surface reflects all of it. The field of view angle of the first scanning optical path formed after the whole reflection increases from the original θ1 to the sum of θ1 and β. By comparison, it can be seen that the original scanning field of view angle is expanded.

[0033] Specifically, the apparatus for expanding the scanning field of view provided by the present application can be used in a lidar to realize the beam angle expansion scanning during its use. At least one optical wedge mirror 2 is installed on at least one reflecting surface of the rotating mirror 1. When the light beam emitted by the light source irradiates the optical wedge mirror 2, the optical wedge mirror 2 can reflect the light beam and increase the field of view angle of the reflected light beam, so as to achieve the purpose of expanding the scanning field of view.

[0034] Moreover, compared with the prior art, under the conditions of the same field of view angle and light source size, the volume of this device is much smaller than that of other optical systems. This makes the installation space it requires smaller, which can meet different usage requirements, can also reduce the size of the overall device, realize the installation and use of the overall device in a smaller space, make the space layout more flexible and efficient, and the relatively small overall device simplifies aspects such as material use and manufacturing process, thereby reducing the production cost.

[0035] Among them, the rotating mirror generally has multiple reflecting surfaces. According to different scanning requirements, the optical wedge mirror 2 can be installed on one or more reflecting surfaces of the rotating mirror 1. The optical wedge mirror 2 can be fixed on the rotating mirror 1 in various ways, such as by using glue bonding, or by using optical cement fixing, or by using other methods.

[0036] In an embodiment of the present application, multiple optical wedge mirrors 2 can also be installed on the same reflecting surface of the rotating mirror 1. The multiple optical wedge mirrors 2 can be arranged side by side or at intervals, and their installation positions can be set according to actual usage requirements, making it more flexible to use. Assuming that 2 optical wedge mirrors are installed on the same reflecting surface, the two optical wedge mirrors 2 are symmetrically distributed along the central axis on the same reflecting surface of the rotating mirror 1. The two optical wedge mirrors 2 both include a front surface and a rear surface. The same reflecting surface of the rotating mirror 1 is respectively connected to the rear surfaces of the two optical wedge mirrors 2; the central axis is perpendicular to the axis of rotation of the rotating mirror 1; along the edge of the rotating mirror 1 towards the central axis direction, the thickness of the optical wedge mirror 2 gradually decreases.

[0037] Specifically, referring to the attached Figure 2 、 4 As shown, the number of optical wedge mirrors 2 provided on one reflecting surface of the rotating mirror 1 is two, and the two optical wedge mirrors 2 are symmetrically installed. The thickness of the two optical wedge mirrors 2 gradually decreases along the edge of the rotating mirror 1 towards the central axis direction. Among them, the central axis is the axis of symmetry of the two optical wedge mirrors 2. Thus, a certain angle is formed between the front surfaces of the two optical wedge mirrors 2. Further, the angle formed between the front surfaces of the two optical wedge mirrors 2 is an obtuse angle, which is convenient for simultaneously reflecting the light beam generated by the light source. The third layer of film 5 is respectively plated on the front surfaces of the two optical wedge mirrors 2. The third film layers 5 of the two optical wedge mirrors 2 both reflect the incident light source beam, realizing the function of increasing the scanning field of view angle.

[0038] For example, the included angle between the front surfaces of two optical wedge mirrors 2 is α. In the prior art, the second initial field of view angle formed by reflecting the light beam of the light source through a single optical wedge mirror is α3. In this application, two optical wedge mirrors 2 are symmetrically installed. When the light beam of the light source irradiates the upper and lower optical wedge mirrors 2 at the same time, the upper optical wedge mirror 2 reflects the incident light and forms a field of view angle of α1, and the lower optical wedge mirror 2 reflects the incident light and forms a field of view angle of α2. The finally formed field of view angle of the second scanning optical path is the sum of α1 and α2, which is greater than the second initial field of view angle α3. Therefore, the function of expanding the scanning field of view angle is realized.

[0039] In the above embodiment, the optical wedge mirror 2 can be an integral structure or an assembled structure. Further, the optical wedge mirror 2 can be an integral structure manufactured integrally, or an assembled structure formed by combining multiple components into a whole.

[0040] Wherein, when two optical wedge mirrors 2 are set as a group, one group or multiple groups can be arranged side by side on at least one reflecting surface of the rotating mirror 1; when one group or multiple groups are arranged side by side, the reflecting surface of the rotating mirror 1 can be partially or completely covered.

[0041] In an embodiment of the present application, two optical wedge mirrors 2 are symmetrically distributed along the central axis on the same reflecting surface of the rotating mirror 1. A connecting mirror 6 is arranged between the two optical wedge mirrors 2. Both optical wedge mirrors 2 include a front surface and a rear surface. The same reflecting surface of the rotating mirror 1 is respectively connected to the rear surfaces of the two optical wedge mirrors 2 and the connecting mirror 6; the central axis is perpendicular to the rotating shaft of the rotating mirror 1; along the edge of the rotating mirror 1 towards the central axis direction, the thickness of the optical wedge mirror 2 gradually decreases. A fourth film layer 7 is arranged on the front surface, and the fourth film layer 7 is a reflecting film.

[0042] Specifically, referring to Figure 5 As shown, installing on the same reflecting surface of the rotating mirror 1 includes two optical wedge mirrors 2 and a connecting mirror 6. The connecting mirror 6 is installed between the two optical wedge mirrors 2. The thickness of the optical wedge mirrors 2 installed on both sides of the connecting mirror 6 gradually decreases along the edge of the rotating mirror 1 towards the central axis direction. Among them, the central axis is the horizontal axis of the connecting mirror 6. An angle is formed between the front surfaces of the two optical wedge mirrors 2. The fourth film layer 7 is respectively plated on the front surfaces of the two optical wedge mirrors 2. The fourth film layers 7 of the two optical wedge mirrors 2 can reflect the incident light beam of the light source, realizing the function of increasing the scanning field of view angle.

[0043] Wherein, when two optical wedge mirrors 2 and a connecting mirror 6 are set as a group, the connecting mirror 6 can directly adopt the reflecting surface of the rotating mirror 1, that is, the two optical wedge mirrors 2 are not connected, and a part of the reflecting surface of the rotating mirror 1 is exposed as the connecting mirror 6.

[0044] Considering the actual reflection effect, the wedge apex angle of the wedge mirror 2 in the present application is 0° ≤ β ≤ 10°.

[0045] The second aspect embodiment of the present application provides a lidar, which includes the scanning field of view expansion device disclosed in any of the above embodiments; thus, the lidar has all the features and beneficial effects disclosed in any of the above embodiments, which will not be elaborated herein.

[0046] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present application shall be included in the protection scope of the present application. The above is only the preferred implementation manner of the present application. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present application, several improvements and modifications can also be made, and these improvements and modifications should also be regarded as the protection scope of the present application.

Claims

1. A scanning field angle expansion device, characterized in that: include: A rotating mirror (1) and at least one optical wedge reflector (2); wherein at least one of the optical wedge reflectors (2) is arranged on at least one reflective surface of the rotating mirror (1); the optical wedge reflector (2) comprises a first surface and a second surface, the rotating mirror (1) is connected to the second surface of the optical wedge reflector (2), the first surface is a beam splitting surface, and the second surface is a reflective surface.

2. The scanning field angle expansion device according to claim 1, characterized in that: A first film layer (3) is arranged on the first surface, and the first film layer (3) is a beam splitting film; and / or, A second film layer (4) is provided on the second surface, and the second film layer (4) is a reflective film.

3. The scanning field angle expansion device according to claim 1, characterized in that: The two optical wedge reflectors (2) are symmetrically distributed on the same reflection surface of the rotating mirror (1) along the central axis; the two optical wedge reflectors (2) each comprise a front surface and a rear surface; the same reflection surface of the rotating mirror (1) is respectively connected to the rear surfaces of the two optical wedge reflectors (2); the central axis is perpendicular to the rotation axis of the rotating mirror (1); and the thickness of the optical wedge reflectors (2) gradually decreases along the edge of the rotating mirror (1) toward the central axis.

4. The scanning field angle expansion device according to claim 3, characterized in that: A third film layer (5) is arranged on the front surface, and the third film layer (5) is a reflective film.

5. The scanning field angle expansion device according to claim 1, characterized in that: The two optical wedge reflectors (2) are symmetrically distributed on the same reflection surface of the rotating mirror (1) along the central axis; a connecting mirror (6) is arranged between the two optical wedge reflectors (2); the two optical wedge reflectors (2) each include a front surface and a rear surface; the same reflection surface of the rotating mirror (1) is respectively connected to the two optical wedge reflectors (2) and the rear surface of the connecting mirror (6); the central axis is perpendicular to the rotating axis of the rotating mirror (1); and the thickness of the optical wedge reflectors (2) gradually decreases along the edge of the rotating mirror (1) toward the central axis.

6. The scanning field angle expansion device according to claim 5, characterized in that: A fourth film layer (7) is arranged on the front surface, and the fourth film layer (7) is a reflective film.

7. The scanning field angle expansion device according to claim 1, characterized in that: At least one wedge reflector (2) is arranged on each reflective surface of the rotating mirror (1).

8. The scanning field angle expansion device according to claim 1, characterized in that: The wedge apex angle of the wedge reflector (2) is 0°≤β≤10°.

9. A laser radar, characterized in that: include: A scanning field of view angle expansion device as described in any one of claims 1 to 8.

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